Underreamer



Feb. 14, 1928.

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Plantea Feb. 14, 192s.

` `UNITED STATES CHARLES` H. BROWN, OF BEEIENBIDGE, TEXAS.

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i Application led May 28, 1926. Serial No. 112,350.

This invention relates to an improvement infunderreamers, and has for its object `.to provide a device of this character wherein a plurality of reamer blades are provided and are so constructed and organized with j the body of the reamerthat they are firmly e section; j

and rigidly sup orted in operative position with their shan is protected against wear. This feature greatlyfacilitates the dressing of the blades, since it makes it ractical to use a dressing form with the b ades when i'e-sliaping or renewing their cutting edges.

Another object of the invention resides 1n the provision of an adjustable carrier for the reamer blades which may be adjusted to take u Wear that occurs.

A urther object is to provide a novel means for expandin e the reamer blades and in conjunctionr wit this means a novel means for releasing tlieexpanding means, the releasing means operating in conjunction with the casing of the well and 1n such manner as to relieve the cutting blades and their mounting or carrier of strains and stresses which would be liable to result in loss of the blades.

A furtherobject is to provide a novel reamerblade structure. j 'A still further'object resides in the provision of an underreamer which may be used to straighten crooked holes.

Other objects and advantages reside in certain novel features of the construction, arrangement and combination of parts which will be hereinafter more fully described and particularly pointed out in the appended claims, reference being had to the accompanying drawings forming a part of this i specification, and in which: e l

Figurel is a view in elevation showing an underreamer constructed in accordance with the present invention,

`Figure 2 is `a view `in section on the line 2 2 of Figure 1, parts being shown in elevation for the sake of illustration,

`Figures 3, 4 and 5 are views in horizontal section on the lines 3 3, 4-4 and 5-5, respectively, of Figure 2,

Figure 6 is abottom plan view of the underreamer,

Figure 7 is a detail perspective view of one of the adjusting pins for adjustably` supporting the blade carrier on the body of the underreamer, i

Figure 8 is a view thereof in transverse Referring to the drawings, it willbe seen that the underreamer embodying the present invention includes a cylindrical body 1 formed with a longitudinally extendin bore or opening 2 which leads to a oint adjacent the upper end of the body dbwn through the lower end thereof.

A pluralityof reamer blades designated generell. at 3 are provided, and are mounted on t e lower end of the body byineans vof an ad'ustable carrier 4. Preferably three reamer lades 3 are provided, and these blades are of identical construction. Each includes a body portion 4l having an upwardly extending shank 5 and a downwardly and outwardly extending cutting portion 6; At the juncture of the shank 5 and the body portion 4, a shoulder 7 is rovided, as the shank 5 is offset inwardly rom the outer peri liery of the body portion 4a. As shown in iguie 6 of the drawing, the corners of the cutters are rounded as shown at 3, the advantage of this rounded formation of the corners residing in the fact that such corners will not burn oil' in the forge, are less liable to check when hardened, and are more easily dressed. The inner periphery of the shank 5 and the body portion 4f Y of each blade are continuous and merge into each other, and together constitute a curved and inclined camming wall 8 which is spaced inwardly and upwardly from the cutting portion 6 of the blade. Adjacent its upper end each shank 5 is provided with a slot 9 which opens out through its inner face. In the assembly, the slots 9 of the blades 3 receivel an outwardly directed annular flange 10 provided on the lower end of the cylinder body 11 of the adjustable carrier 4. The flange 10 is loosely fitted in the slots 9 to permit the reamer blades to partake of their operative movements and yet to hold them against displacement from the body and a ainst lon itudinal movement with respect t reto. T e body portion 11 of the carrier 4 also has a pair of spaced annular flanges desi .nated at 12 and 13 and located above the ange 10. The flanges 12 and 13 receive between thema pair of su ignated generally at 14. bod portion 11 vlocated between the pair of `anges 12 and 13 has a pair of faces 11,

the members ofthe pair of faces 11 being opposite each other, the faces 11b being `orting pins des-` he section of the` spaced angularly 60 from the faces 11a. In the drawing, the pins are shown cooperating with the faces 11b, but by shifting the carrier in the casing the faces 11n may be brought into coaction with the pins, thereby distributing the wear in that in reassembling the blades with thereamer, their positions may be positively changed and the bottom of the body 1 may be worn evenly,

Each pin 14 has rounded ends designated at 15 and 16 and engage' bearings 17 and 18 respectively provided on the body portion 1 of the underreamer as shown to advantage in Figure 4. intermediate the journals 15 and 16 each pin 14 has a plurality of flat faces designated at 19, 20 and 21, the faces 19, 20 and 21 being eccentric with respectto the pin and being located at different radial distances from the center or axis of rotation of the pin. The ends 15 of the pins are provided with openings to coact with screws or other fastening means for holding the pins in any adjustmentfor preventing accidental displacement thereof. lt is obvious that when the surface 19 is engaged with the flange 12 of the body portion 11 of thecarrier 4, the carrier will be adj ustably secured in one position on the body portion 1 of the reamer, whereas when the surfaces 2O and 21 are brought into engagement with the carrier, this carrier will be supported in other positions, and this provides the adjustment necessary to tal-re up wear.

The carriers 4 are preferably provided in sets, yeach set for each tool consisting of four carriers. The carriers of each set are of similar construction but dider in the spacing of the flanges 10 and 13, the body portion 11 of the carriers of the set being successively shorter. 1With such a set of carriers after the pins 14 have been adjusted to take up the rmaximum amount of wearthat they can handle, which is'usually one-fourth of an inch, then a shorter carrier 4 is put into the tool and another one-fourth inch 0f wear may be taken up. This process is repeated until all the sets of carriers have been used.

Expanding means is provided for the reamer blades, and comprises a mandrel 25 extending axially through the opening of the body 1 and having a frusto-conical expanding member 26 welded or otherwise suitably secured to enlargements 2'? and 28 provided on the mandrel. The periphery of this frusto-conical expanding member 26 is adapted to engage the curved and correspondingly formed walls 8 of the reamer blades. Spring means is provided for urging the mandrel 25 to such position that its expanding member 26 engages the reamer blades and expands the same, and this spring means preferably consists of va compression coil spring 29, the lower 'end of which rests on the carrier 4, andthe upper end of which engages an adjustable abutment on the man-y drel which is preferably in the form of a nutI 3() threadedly engaged with the mandrel and held in position by a lock nut 31.

lVhen the rean'ie'r blades are er;L anded by the expanding member 26, the outer periph- 4cries of their Shanks 5 snugly 'engage the inner wall of the body portion 1, as illustrated in Figure 5, and the shoulders 7 of the blades abut against the lower end of the body of the underreai'ner. ln this way Vthe reamer blades are rigidly and securely held in position and very little if any wear can occur except on the cutting edges.

Releasing means is provided for the expanding means and consists of a pair of riders or shoesftl lixed on the lower 'endsof arms 36 having their upper portions inturned and pivotally connected, as at 37, to a supporting and connecting member 38 which has its lower endflanged and recessed, as at 38a and fitting over the upper rounded end 40 of the mandrel 25. The supporting inember 38 is held engaged with the mandrel by means of a light coil spring 41.

The shoes 35 have rearwardly directed flanges 42 inset from their edges and terminating in angularly olfset lips 43 which coact with the body 1 of the reamer to limit displacement of the shoes in their operative position.

As shown in Figures 1, 2 and 8, the shoes 35 operate in slots 44 provided in the body 1 and extending from the internal opening of the body out through the periphery thereof.

At their lower ends the slots 44 have enlargements 45. Viith this arrangement when the shoes operate in the slots 44 they are held against any substantial degree of transverse displacement by virtue of the engage ment of the edges 4-2 of the shoes with the outer iiiarginal walls of the slots 44 and the engagement. of the flanges 43 with vthe inner marginal walls of said slots. The outnf'ard displacementvof the shoes is always limited by the action of the flanges 43 which have suiiicient extent to engage the inner marginal walls oil the enlargements 45 as well as the inner marginal walls of the slots 44. The enlargements 45 are of suliicient size, however, to accommodate the shoes 35 when the shoes 35 are positioned in opposed relation with the enlargen'ients. With this ar angement when the underreamer is pulled up to the casing shoe, the shoes 35 engage the casing shoe and are held stationary while the body of the mandrel continues to move upwardly. This results in a compression of the spring 29 and the lowering of the ex panding` mandrel, permitting the cutters to move to an inoperative position out of the way of the casing shoe. This action continues until the shoes 35 cbme into alignment ith the enlargements 45 whereuponthe shoes 35 move into the body of the underreamer and in so doing are disengaged from the casing shoe and consequently move upwardly with the body of the underreamer. The assembly of the shoes is brought about by inserting the shoes or riders with their arms up through the lower end 0f the body and passing'the shoes outwardly through the enlargements ofthe slots 44.

The body l of the underreamer has a tool joint 46 at its upper end, and below the tool joint the body l is provided with a tapered and externally threaded portion 47 designed to receive a pipe or string oit tubing 48 which co-acts with the well casing and serves as a guide when the underreamer is used to straighten crooked holes;

l claim :m

l. An underreamer including a body having 4an opening therein extending out through the lower end thereof, reamer blades having shanks extending up into the lower end of the body and having cutting portions projecting below the body, means cooperable with the shanks of the blades for mounting the blades on the body, including a carrier having means interengageable -with the shanks of the blades, and supporting pins adjustably mounted on the body and engageable with the carrier for supporting the same in any one of a plurality of adjustments, and means for expanding the blades.

2. An underreamer including a body having an opening therein extending out through the lower end thereof, reamer blades having shanks extending up into the lower end ot `the body and having cutting portions projecting below the body, means cooperable with the shanks of the blades for mounting the blades on the body, including a carrier having means interengageable with the Shanks of the blades, and supporting pins llaving portions rotatably mounted on the body and having fiat `fac/es located at diflierent distances from the centers of the pins and selectively engageable with the carrier ior supporting the same in a plurality of adjusted positions, and means for expanding the blades. i

3. An underreamer comprising a body, a plurality of reamer blades, means for` mounting the reamer blades on the end of the body tor operative movement in cutting walls of the bore, means for ex anding the reamer blades including a man rel, and an expanding member fixed on t-he mandrel and cooperative with the reamer blades, spring means for urging the mandrel to such position as to cause the expanding member to expand the blades, and means for releasing the expanding means and including a pair of shoes, said body having slots through which the shoes project, said shoes having `ianges engageable with the edges of the of the operation.

- 4. An underreamer comprising a bod plurality of reamer blades, means mounting the reamer blades on the end of the body for operative movement, means for expanding the reamer blades including a mandrel, und anfexpanding member fixed on the mandrel and cooperative with the reamer blades, spring means for urging the mandrel to such position as to cause the expanding member to expand the blade, and means for releasing the expanding means and including a pair of shoes, said body having slots through which the shoes project, arms carrying the shoes, and a combined connecting and supporting member pivoted to the arms and engaging the mandrel, and a spring for maintaining the combined connecting and supporting member engaged with the mandrel.

5. An underreamer including a body having an opening therein extending out through the lower end thereof, reamer blades having Shanks extending up into the lower end of the body and having cutting portions projecting below the body, means cooperable with the shanks of the blades Jfor mounting the blades on the body, including a carrier having means interengageable with the Shanks of. the blades, and supporting pins adjustalily mounted on the body and engageable with the carrier for supporting the same in any one of a plurality of adjustments, said carrier having angular spaced pairs of lateral faces selectively engageable with said pins, and means for ex panding the blades.

6. An underreamer including a body hav' ing an opening therein extending out through the lower end thereof, reamer blades having shanks extending up into the lower end of the body and having cutting portions projecting below the body, means cooperable with the Shanks of the blades for mounting the blades on the body, including a carrier having means interengageable with the shanks of the blades, and means adjustably mounted on the body and engage able with the carrier for supporting said carrier in any one of a plurality of adjustments, said carrier having angular spaced pairs of lateral faces selectively engageable with said means, and means for expanding the blades. CHARLES H. BROWN.

Y a' for 

